/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

/* Expose glibc-specific EAI_* error codes. Needs to be defined before we
 * include any headers.
 */
#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif

#include "uv.h"
#include "internal.h"

#include <errno.h>
#include <stddef.h> /* NULL */
#include <stdlib.h>
#include <string.h>

/* EAI_* constants. */
#include <netdb.h>

int uv__getaddrinfo_translate_error(int sys_err)
{
    switch (sys_err) {
    case 0:
        return 0;
#if defined(EAI_ADDRFAMILY)
    case EAI_ADDRFAMILY:
        return UV_EAI_ADDRFAMILY;
#endif
#if defined(EAI_AGAIN)
    case EAI_AGAIN:
        return UV_EAI_AGAIN;
#endif
#if defined(EAI_BADFLAGS)
    case EAI_BADFLAGS:
        return UV_EAI_BADFLAGS;
#endif
#if defined(EAI_BADHINTS)
    case EAI_BADHINTS:
        return UV_EAI_BADHINTS;
#endif
#if defined(EAI_CANCELED)
    case EAI_CANCELED:
        return UV_EAI_CANCELED;
#endif
#if defined(EAI_FAIL)
    case EAI_FAIL:
        return UV_EAI_FAIL;
#endif
#if defined(EAI_FAMILY)
    case EAI_FAMILY:
        return UV_EAI_FAMILY;
#endif
#if defined(EAI_MEMORY)
    case EAI_MEMORY:
        return UV_EAI_MEMORY;
#endif
#if defined(EAI_NODATA)
    case EAI_NODATA:
        return UV_EAI_NODATA;
#endif
#if defined(EAI_NONAME)
#if !defined(EAI_NODATA) || EAI_NODATA != EAI_NONAME
    case EAI_NONAME:
        return UV_EAI_NONAME;
#endif
#endif
#if defined(EAI_OVERFLOW)
    case EAI_OVERFLOW:
        return UV_EAI_OVERFLOW;
#endif
#if defined(EAI_PROTOCOL)
    case EAI_PROTOCOL:
        return UV_EAI_PROTOCOL;
#endif
#if defined(EAI_SERVICE)
    case EAI_SERVICE:
        return UV_EAI_SERVICE;
#endif
#if defined(EAI_SOCKTYPE)
    case EAI_SOCKTYPE:
        return UV_EAI_SOCKTYPE;
#endif
#if defined(EAI_SYSTEM)
    case EAI_SYSTEM:
        return -errno;
#endif
    }
    assert(!"unknown EAI_* error code");
    abort();
    return 0; /* Pacify compiler. */
}

static void uv__getaddrinfo_work(struct uv__work* w)
{
    uv_getaddrinfo_t* req;
    int err;

    req = container_of(w, uv_getaddrinfo_t, work_req);
    err = getaddrinfo(req->hostname, req->service, req->hints, &req->addrinfo);
    req->retcode = uv__getaddrinfo_translate_error(err);
}

static void uv__getaddrinfo_done(struct uv__work* w, int status)
{
    uv_getaddrinfo_t* req;

    req = container_of(w, uv_getaddrinfo_t, work_req);
    uv__req_unregister(req->loop, req);

    /* See initialization in uv_getaddrinfo(). */
    if (req->hints)
        uv__free(req->hints);
    else if (req->service)
        uv__free(req->service);
    else if (req->hostname)
        uv__free(req->hostname);
    else
        assert(0);

    req->hints = NULL;
    req->service = NULL;
    req->hostname = NULL;

    if (status == -ECANCELED) {
        assert(req->retcode == 0);
        req->retcode = UV_EAI_CANCELED;
    }

    if (req->cb)
        req->cb(req, req->retcode, req->addrinfo);
}

int uv_getaddrinfo(uv_loop_t* loop,
    uv_getaddrinfo_t* req,
    uv_getaddrinfo_cb cb,
    const char* hostname,
    const char* service,
    const struct addrinfo* hints)
{
    size_t hostname_len;
    size_t service_len;
    size_t hints_len;
    size_t len;
    char* buf;

    if (req == NULL || (hostname == NULL && service == NULL))
        return -EINVAL;

    hostname_len = hostname ? strlen(hostname) + 1 : 0;
    service_len = service ? strlen(service) + 1 : 0;
    hints_len = hints ? sizeof(*hints) : 0;
    buf = uv__malloc(hostname_len + service_len + hints_len);

    if (buf == NULL)
        return -ENOMEM;

    uv__req_init(loop, req, UV_GETADDRINFO);
    req->loop = loop;
    req->cb = cb;
    req->addrinfo = NULL;
    req->hints = NULL;
    req->service = NULL;
    req->hostname = NULL;
    req->retcode = 0;

    /* order matters, see uv_getaddrinfo_done() */
    len = 0;

    if (hints) {
        req->hints = memcpy(buf + len, hints, sizeof(*hints));
        len += sizeof(*hints);
    }

    if (service) {
        req->service = memcpy(buf + len, service, service_len);
        len += service_len;
    }

    if (hostname)
        req->hostname = memcpy(buf + len, hostname, hostname_len);

    if (cb) {
        uv__work_submit(loop,
            &req->work_req,
            uv__getaddrinfo_work,
            uv__getaddrinfo_done);
        return 0;
    } else {
        uv__getaddrinfo_work(&req->work_req);
        uv__getaddrinfo_done(&req->work_req, 0);
        return req->retcode;
    }
}

void uv_freeaddrinfo(struct addrinfo* ai)
{
    if (ai)
        freeaddrinfo(ai);
}
